Hi,Sometimes after even a 20-30 mile trip I will get a whiff of a weird smell coming out from under the coach. It smells like burning plastic or something. It seems to come from the rear wheel wells. The wheels and tires are warm or hot to the touch. It goes away quickly and I havent noticed any issues with breaking, or any noises. Before I take it in for service, any thoughts on what it could be? We did have ants infesting the insulation and would find little white piles of "dust" under the RV but we have taken care of that with some ant traps. I thought maybe it was plastic burning off from those droppings but it could be brakes or axle I guess?This is on a 2008 Winnebago Outlook 31C with only 10k miles.

A common problem is the seals for the axles will leak. Small amounts of rear end grease will get on the brake shoes or drums, if it's a small amount of grease it won't always affect braking performance. This can result in a smell that I guess could be mistaken for burnt plastic.

Would getting the bearings repacked and seals replaced be a good idea?

Really the best idea is to take it in and have the the shop identify the source of the smell. Then you can decide if you need or want to pack the bearings.

I would look for a wiring harness close to the exhaust.Look at inside of the rear wheels for signs of a fluid leak.

You didn't leave the parking brake on by chance?You say the tires are hot as well... Have you checked the tire pressure, to ensure it's appropriate for your rear axle weight?Axle seals are not usually a problem on the E450. And you don't have drum brakes so it can't be brake cylinders. Rear wheel bearings don't get "re-packed" because they are lubricated by the differential oil.

Smell and heat from rear wheel wells | Good Sam Community

the_bear_II
Explorer
Sep 17, 2019
A common problem is the seals for the axles will leak. Small amounts of rear end grease will get on the brake shoes or drums, if it's a small amount of grease it won't always affect braking performance. This can result in a smell that I guess could be mistaken for burnt plastic.
BigCanoe
Explorer
Sep 17, 2019
Would getting the bearings repacked and seals replaced be a good idea?
opnspaces
Navigator II
Sep 17, 2019
Really the best idea is to take it in and have the the shop identify the source of the smell. Then you can decide if you need or want to pack the bearings.
enblethen
Nomad
Sep 17, 2019
I would look for a wiring harness close to the exhaust.
Look at inside of the rear wheels for signs of a fluid leak.
carringb
Explorer
Sep 17, 2019
You didn't leave the parking brake on by chance?

You say the tires are hot as well... Have you checked the tire pressure, to ensure it's appropriate for your rear axle weight?

Axle seals are not usually a problem on the E450. And you don't have drum brakes so it can't be brake cylinders. Rear wheel bearings don't get "re-packed" because they are lubricated by the differential oil.
BigCanoe
Explorer
Sep 17, 2019
I will check the tire pressure. The parking brake is released, but no idea if its dragging or not? Ok didnt know that about the bearings!
STBRetired
Explorer
Sep 17, 2019
Have you slithered under the RV to look? I would suspect something hanging down near the exhaust. Perhaps a piece of road debris? With all the garbage laying on some roads, it's not hard to pick something up.
midnightsadie
Explorer II
Sep 17, 2019
your wheels should NOT BE HOT.
BigCanoe
Explorer
Sep 17, 2019
Even the tires are warm. I will check the tire pressure first.
CloudDriver
Explorer
Sep 17, 2019
An 11 year old chassis with only 10k miles, which means it sat alot. My first thought would be a sticky brake caliper.